In Age of Rivals, there are over 200 cards across 9 different types. The card's special ability often targets other cards based on their types.
Infantry cards, like Pikemen, attack the enemy. They have attack, defense and their special abilities will often modify their attack/defense stats based on the enemy card type. In the case of Pikemen, it has 4 more attack against Mounted cards.
Their primary resource is iron.
Mounted cards, like the Mounted Guard, also primarily attack the enemy. Their special abilities will often modify either their own attack/defense stats or other cards' stats. In the case of the Mounted Guard, it gives 3 more defense to a friendly Infantry card.
Their primary resource is horse.
Ranged cards, like Light Catapults, damage specific targets. Their special abilities will define which enemy card they will attack. In the case of Light Catapults, it has 4 attack versus Fortified enemy cards.
Their primary resource is wood.
Underworld cards, like the Common Thief, weaken the enemy city. Their special abilities define exactly how they will target the enemy. In the case of the Common Thief, it will steal 3 gold after the war phase has ended.
Their primary resource is training.
Artistic cards, like the 100 Days Festival, provide culture to your city. Culture translates directly into victory points, provided the card doesn't get knocked out or ruined. The artistic card special abilities typically revolve around giving you more culture. In the case of the 100 Days Festival, it has 3 extra culture for each other artistic card in your city.
Their primary resource is crafts.
Holy cards, like the Temple of Wisdom, also provide culture to your city, which gives you victory points during the scoring phase. The Temple of Wisdom in particular has 3 extra culture if you have 3 cards of type Holy in your city during the round.
Their primary resource is paper.
Civic cards, like the Gambling Hall, provide benefits to your city. Their special abilities vary a lot, but in the case of the Gambling Hall specifically will either gain 1 or 5 gold at the end of the round. Who doesn't like a little game of chance?
Their primary resource is gems.
Fortified cards, like the Fort of Last Resort, protect your city. They have a lot of defense and no attack. Their special abilities focus on defense as well. In the case of the Fort of Last Resort, it has 1 extra defense and 2 culture points for each enemy attacker (any card with an attack stat.)
Their primary resource is stone.
Economic cards provide resources and income to your city. In the case of Southern Trade it increases your income for the following rounds by 1 gold. It also gives you discounts for cards that cost paper or horse.